1. Technical Field
The present invention relates to a ball screw and a power steering apparatus.
2. Related Art
As a ball screw circulation type, an end deflector type is known. In this method, a circulation path through which a ball is circulated is formed in a nut. The nut has, at respective opposite ends thereof, end deflectors having a function to scoop the ball from a spiral groove in the nut into the circulation path or to return the ball from the circulation path to the spiral groove in the nut.
Patent Literature 1 (JP-A-2012-154437) discloses a ball screw including an end deflector of a two-division structure.
The end deflector is mounted in the nut by being housed in a housing portion formed in the nut. In this case, when there is backlash between the end deflector and the housing portion or between division components if the end deflector has a divided structure, the backlash may cause noise or increased friction with the ball.
To suppress the backlash in a structure where the end deflector is placed in the housing portion by press fitting, the end deflector may be more tightly press-fitted into the housing portion for housing. However, this presents a problem in that workability during assembly is deteriorated.